In 1972, Apollo XVII astronauts Gene Cernan and Harrison Schmitt landed on the moon for a three-day exploration.

In 1983, 30,000 women tried to rip down fences around a U.S. cruise missile base at Greenham Common, England.

In 1984, a nativity scene was displayed near the White House for the first time since courts ordered it removed in 1973.

In 1989, Bulgarian leader Peter Mladenov set a May 31 deadline for free elections and called for a constitution that did not guarantee the Communist party a dominant role in the Eastern European country.

In 1992, the three major TV networks agreed on joint standards to limit entertainment violence by the start of the next fall's season.

In 1993, parliamentary elections were held in Russia.

Also in 1993, Eduardo Frei Ruiz-Tagle of the ruling center-left Coalition of Parties for Democracy won Chile's presidential election.

In 1994, up to 40,000 Russian troops invaded Chechnya, a semi-autonomous republic on Russia's border with Georgia, to put down a secessionist rebellion.

In 1995, two Japanese cult members admitted they had released the toxic sarin gas in Tokyo subway trains the previous March that killed 12 people.

In 1997, a federal judge in Washington ruled that Microsoft Corp. could not bundle its Internet Explorer with Windows 95.

In 1998, the International Olympic Committee began an internal investigation into rumors that bribes had been offered by cities seeking to be chosen as sites for the Olympic games.

In 2001, the U.S. filed its first charges in connection with the Sept. 11 terrorist attacks, accusing Zacarias Moussaoui, a French citizen of Moroccan descent, of conspiring with others to carry out the assault.

In 2003, by this date, the flu had spread significantly over 24 states and demand was outdistancing the available supply of vaccine.

In 2004, Vienna doctors treating the mystery illness of Ukrainian opposition leader Viktor Yushchenko determined he was poisoned by dioxin while campaigning for president.

Also in 2004, a study indicated that U.S. teen sexual activity dropped significantly since 1995.

A thought for the day: Paul Valery said, "That which has always been accepted by everyone, everywhere, is almost certain to be false."

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